Project Summary/Abstract Importance: Epilepsy is one of the most common neurological disorders affecting 2.3 million Americans. Persons with epilepsy (PWE) experience excessive burden of comorbid conditions. Despite treatment, seizure continues to occur aggravated by comorbid diseases. This study will determine prevalence rates in population subgroups and the risk factors of comorbid diseases. Objectives (with specific aims &hypotheses [Ho]): 1. Compare the magnitude and distribution common comorbid conditions among PWE (Case group) relative to persons with extremities fracture (EF) and delirium/syncope (DS) (Comparative Groups).HA1a.We predict that compared to persons with EF and DS, PWE will have significantly higher rate ratios (RR) of comorbid conditions. HA1b. We predict that among PWE, blacks will have significantly higher RR of comorbid conditions than whites. HA1c. We predict that among PWE, rural and underserved county residents will have significantly higher RR of comorbid conditions. HA1d. We predict that there is inverse relationship between socioeconomic (SES) gradient and the number of comorbid conditions among PWE. 2. To determine the implications of epilepsy comorbidity on mortality and seizure conditions. HA2a. We predict that PWE with comorbid condition are more likely to have higher mortality. HA2b. We predict that PWE with comorbid condition are more likely to have higher SUDEP than those without. HA2c. We predict that PWE with more counts of comorbid conditions are more likely to have higher frequency of seizures. 3. To determine the association of comorbidities and individual characteristics, AEDs, recency of the onset of epilepsy, and type of seizure. HA3a. We predict that the risk of psychiatric comorbidites is socioeconomic dependent. HA 3b: We predict that >2 AEDs are associated with somatic comorbidites. HA 3c: We predict that refractory cases of epilepsy will have fewer epilepsy comorbidities compared to pre-surgery. 4. To determine the population attributable risk of hospitalizations accounted by epilepsy comorbidities and the direct medical care cost. HA 4a. We predict that PWE with comorbid conditions will have higher rates of hospitalization than those PWE without comorbid conditions. HA 4b. We predict that direct medical care cost of PWE with comorbid conditions is significantly higher than those without comorbid conditions Study Design: A two phase study: Phase I. Prevalence study of comorbid conditions among PWE statewide. Phase II. Retrospective-cohort study of PWE and two sets of comparison controls, (EF) and (DS). Setting: All nonfederal hospitals, EDs, and outpatient clinics and a Level IV Comprehensive Epilepsy Center (CEC). Participants: A total of 33,439 PWE and a subset of at least 2,000 patients evaluated at the CEC. Outcome measures: Rate ratios of comorbid conditions;Seizure conditions and mortality risk as a function of comorbid conditions;and Estimates of direct medical care cost and population attributable risk of hospitalization.